Lassa Fever Cases Rise in Nigeria with 1119 Confirmed

The Nigeria Centre for Disease Control and Prevention has reported a significant number of Lassa fever cases in 2025, with 1,119 confirmed infections and 206 deaths recorded nationwide. According to the agency’s latest situation report, young adults are the most affected age group, with individuals between 21 and 30 years old accounting for the highest burden of confirmed cases.

The report, which covers the period from December 15 to 21, 2025, reveals that males are slightly more affected than females, suggesting potential gender differences in exposure or health-seeking behavior in high-risk communities. The case fatality rate stands at 18.4%, higher than the 16.4% reported during the same period in 2024.

In the past week, 21 new confirmed cases and five deaths were reported, representing a modest decline in new infections compared to the previous week. The cases were recorded in several states, including Bauchi, Ondo, Taraba, Edo, Kogi, Ebonyi, and Plateau, with a total of 21 states and 105 local government areas affected.

Four states – Ondo, Bauchi, Edo, and Taraba – account for 88% of all confirmed infections, with Ondo State alone contributing 35% of the nationwide total. The Nigeria Centre for Disease Control and Prevention identifies late presentation at treatment facilities, poor health-seeking behavior due to high treatment costs, and poor environmental sanitation in high-burden communities as key challenges affecting outbreak control.

Lassa fever is an acute viral hemorrhagic illness transmitted mainly through contact with contaminated food or household items, as well as human-to-human transmission. The disease can be prevented through proper environmental sanitation, avoidance of contact with infected rodents, and early diagnosis and treatment.

To combat the outbreak, the NCDC is coordinating a multi-sectoral national response, including surveillance, case management, laboratory support, and infection prevention and control activities. The agency urges healthcare workers to maintain a high index of suspicion for Lassa fever and ensure early diagnosis and treatment, while calling on state authorities to strengthen risk communication and community engagement. As the situation continues to evolve, the NCDC will remain vigilant in its efforts to control the outbreak and prevent further spread of the disease.